CentOS 7 / RHEL 7 / Fedora Linux (many other modern distor) uses Systemd. It is a system and service manager for Linux operating systems. In newer distro such as CentOS7/RHEL7 systemd replaces Upstart as the default init system. [donotprint]
| Tutorial details | |
|---|---|
| Difficulty level | Easy |
| Root privileges | Yes |
| Requirements | CentOS/RHEL 7 Fedora Linux latest |
| Est. reading time | 2m |
In older versions of CentOS or Red Hat Enterprise Linux, you used init scripts located in the /etc/rc.d/init.d/ directory. These init scripts were typically written in Bash, and allowed the system administrator to control the state of services and daemons in their system. In CentOS/RHEL 7, these init scripts have been replaced with service units.
CentOS 7 / RHEL 7 networking service name
To bring up/down networking service you need to use the network.service.
Say hello to systemctl command
Use this command to control the systemd system and act as a service manager.
CentOS 7 / RHEL 7 get status of network service
sudo systemctl status network.service
OR
sudo systemctl status network
Sample outputs:
Fig.01: CentOS / RHEL 7 Networking Service Status Command
CentOS 7 / RHEL 7 restart network service
sudo systemctl restart network.service
OR
sudo systemctl restart network
CentOS 7 / RHEL 7 start network service
sudo systemctl start network.service
OR
sudo systemctl start network
CentOS 7 / RHEL 7 stop network service
sudo systemctl stop network.service
OR
sudo systemctl stop network
Sample outputs:
Animated gif 01: systemctl command in action
A note about old service and chkconfig command
The service and chkconfig commands are still available in the system and work as expected, but are only included for compatibility reasons and should be avoided as may be dropped in future release.
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Hi,
Nice start with CentOS/RHEL 7. Waiting for more updates from you. As your blog is very helpful for us….
Regards
Hi there,
Before anything else good article and thanks for it ;) just a quick add to it, Firewall in CentOS 7 works a bit differently than previous ones has I noticed, so if anybody is having difficulty accessing the Nagios web GUI at the end, try adding this firewall rules for ports 80 (http) and 443 (https):
[root@nagios-server /]# firewall-cmd –permanent –zone=public –add-service=http
[root@nagios-server /]# firewall-cmd –permanent –zone=public –add-service=https
[root@nagios-server /]# firewall-cmd –reload
And after that you should now be able to access the web GUI with no problems ;)
Best ragards
Just in case anyone is wondering what is the equivalent of the chkconfig servicename on/off is:
systemctl enable servicename
systemctl disable servicename
The Fedora people put a nice cheatsheet over here https://fedoraproject.org/wiki/SysVinit_to_Systemd_Cheatsheet
I like Centos 7 so far but Systemd can die in a fire. I want my SysV init scripts back.
@ Daniel, I second this motion. Hey everybody, let’s take something that has worked perfectly for 20+ years and change it for no good reason.
@Daniel, third this motion, systemd is incompatible with SysV which proved pretty clean and easy to maintain. I’m afraid systemd will end up another upstart.
really like SysV scripts, and I am afraid that it is not easy to upgrade from redhat/centos 6.x to 7.
Your firewall commands didn’t work with my fresh CentOS 7 install.
I had to do the follwoing to access my webserver/httpd remotely:
[code]firewall-cmd –permanent –zone=public –add-port=80/tcp
systemctl restart firewalld.service[/code]
A lot of new things in CentOS 7. I think, it isn’t easy for IT people to change the configurations from CentOS 6.X to 7.0 (short but big change!?), not easy to follow in this time.
or you can jus disable firewell-cmd and use iptables instead , after you install the it with
yum install iptables-services
I wanna ask something about network manager, how to lock network manager only root can change or edit the setting, or must input root password to edit the network setting from network manager.
because if user click network manager icon, user can change the setting without permission.
prevent user from changing the network setting.
thank you
regards
Hi,
I just started to use CentOS 7, but I see some problems with network stop/start/restart.
The current implementation does not allow to retain an address if the interface is down (useful of the machine is a gateway and it is accessed from the ‘still-alive’ connection), probably I need to use a loopback address for this purpose.
Can anyone tell me if there’s a method to restart a single interface, other than nmtui ?
only the plain old ifdown/ifup ?
TIA
if you do a few commands
Look at nmcli con commands they are pretty easy
Hi
thank you
I dont mind this new way to control programs with 1 caveat. I the old system if you were not quiet sure of the spelling of the service (i.e spamassassin or ist spamasissin or etc etc) all you had to do was type /etc/init.d/spam and a couple of tabs and you could easily get it. I made a link to /etc/init.d called apps so it was even easier just typed /apps/spam and got it that way. I can not see an easy way to do this in the new system otherwise no problems. (maybe some one can show me)